Healthcare portals are becoming increasingly popular with Internet users since they play an important role in supporting interaction between individuals and healthcare organizations with a Web presence. Additionally, many of these organizations make use of knowledge management mechanisms on their healthcare portals to manage the abundance of health-related information, and exchange and share information with their users. Hence, the objective of this study is to evaluate the extent to which knowledge management mechanisms can be supported by healthcare portals. This paper presents a comprehensive analysis of knowledge management mechanisms used by 60 healthcare portals to access, create and transfer knowledge. We selected healthcare portals from two geographical regions (i.e. North America and Asia) and three healthcare portal provider categories (i.e. hospital, government, non-government). We found that healthcare portals from different geographical regions and portal provider categories differed significantly on how they used their portals to access, create and transfer knowledge. The results of this study can be used by healthcare portal providers to enhance their knowledge management practices and improve their customer service relationships. (Contains 13 tables and 4 figures.)